VU meter explained

[inperson]

Are VU meters affected by the efficiency of the speakers used? What I mean is on my Nikko 1200 amp the meters barely bounce at all. They stay down around the -20 mark, sometimes going up to -10 but my speakers are around 98db so only a little bit of volume is needed for them to be plenty loud. Are they operating correctly?

 

[Gigantic]

Are VU meters affected by the efficiency of the speakers used? What I mean is on my Nikko 1200 amp the meters barely bounce at all. They stay down around the -20 mark, sometimes going up to -10 but my speakers are around 98db so only a little bit of volume is needed for them to be plenty loud. Are they operating correctly?

They’re effected by the amp output, so they’d barely move with 98bD speakers at polite listening levels. Some VU meters gave sensitivity adjustment screws, typically micropotentiometers, to adjust sensitivity, but I don’t know if that is the case with your Nikko 1200

 

[twiiii]

One of the first lessons I learned about VU meters back in the 60's was that A professional VU Meter could have errors of 18 db regarding peaks. It was one reason professional tape recorders were calibrated to have 3 % distortion continuous at either 400 or 700 HZ at + 6 db above 0 db on the meter. The proven thinking was then you could have at least 6 db above 0 db without to much distortion for longer peaks. We started out in the early 60's with 185 nWeb on the alignment tapes to match the playback and recording levels. BY the late 70's before digital came along 512 nWebs was the accepted standard with improvements in tape and electronics. Or about 8 db improvement. Plus high frequecy distortions had been much reduced by the new back coated tapes from Maxell and TDK. So keeping the old standards we now 14 db of head room to make up for the 18 db lie by meters. Of course by then Technology gave everyone a better and more accurate way of seeing the true levels. LED bars, and light weight meter assemblies with faster and more accurate peak reading capabilities. These advanced ments allowed Mcintosh to place meters on their second generation of SS amps that were very accurate and if followed would keep amps power output from being compromised. But Mcintosh had also developed Power Guard to prevent SS amplifiers from clipping. Their newest tube amps have a circuit that prevents the tubes from being over stressed now also. Tube Power Guard in some respects.

 

[inperson]

They’re effected by the amp output, so they’d barely move with 98bD speakers at polite listening levels. Some VU meters gave sensitivity adjustment screws, typically micropotentiometers, to adjust sensitivity, but I don’t know if that is the case with your Nikko 1200

Yes, my Nikko has adjustments on the back but they are turned all the way up and get just a slight bounce from my Opera Consonance M15 speakers. I hooked up my Klipsch Heresy speakers and the meters had a bit more bounce to them. Thanks!